In the array of defensive weaponry, there is no viable, safe defensive alternative to the firearm. While society is increasingly reluctant to combat violent behavior with violent countermeasures, this same society demands a greater level of protection against those individuals and groups who actively employ violent means.
The human hesitancy to dispatch a potentially lethal force is a significant cause of violent injury to police in the line of duty. A police officer may be left without an alternative to lethal force, especially when the attacker is closing at speeds sufficient to cover 15 feet in less than a second.
Handheld aerosol devices have been available for many years. However, at present there are no standards for handheld aerosol devices. This has left the commercial marketplace with substandard devices which are incapable of delivering accurate, respirable aerosol doses directly to the lungs or a metered topical spray to the face, skin, eyes, nasal cavity, mouth and throat. Uncertainty as to the effectiveness of these devices results in the tendency to overdose an attacker to insure absolute containment and control.
Prior art handheld aerosol devices typically utilize oleoresin capsicum (OC), commonly known as pepper spray, in an oil-based solution. Standard commercial atomizers do not effectively disperse such solutions into a reliable mist. As a result, most solutions contain about 5% active agent, whereas an optimized solution should be about three times as concentrated. Furthermore, most standard commercial atomizers create droplets that are much too large to be effectively taken deeply into the lung, even though these aerosol devices would have greater effect if targeted for the lungs. The effectiveness of aerosol spray devices is ultimately measured by the delivery of bioactive agents, such as OC aerosols, directly into the lungs at less than 10 micron particle size, which is necessary for inhalation efficacy. The inflammation of the oropharynx, bronchioles, alveolar ducts, and mucus membranes occurs on contact with typical bio-active chemical agents such as OC aerosol. The physiological impact due to lung and respiratory tract inflammation immediately pulls blood flow from the body's extremities at rates sufficient to incapacitate continued muscular exertion in most people.
Personal defense devices which utilize an aerosol spray arc disclosed, for example, in U.S. Pat. No. 3,602,399 issued Aug. 31, 1971 to Litman et al; U.S. Pat. No. 4,624,389 issued Nov. 25, 1986 to Ang; U.S. Pat. No. 5,000,347 issued Mar. 19, 1991 to Tran; U.S. Pat. No. 5,397,029 issued Mar. 14, 1995 to West; U.S. Pat. No. 5,509,581 issued Apr. 23, 1996 to Parsons; and U.S. Pat. No. 5,570,817 issued Nov. 5, 1996 to Anderson et al.
Another type of non-lethal personal defense device involves the application of an electrical shock to the attacker. A device for projecting two continuous parallel streams of conductive fluid is disclosed in U.S. Pat. No. 3,971,292 issued Jul. 27, 1976 to Paniagua. The streams of fluid are held at different electric potentials so that when they impact a target, an electric circuit is completed, thereby causing a current to pass through the target.
All known prior art non-lethal defense devices have had one or more drawbacks, including but not limited to lack of effectiveness in incapacitating the attacker, difficulty in use under highly stressful conditions, risk of serious injury or death to the attacker and lack of reliability. Accordingly, there is a need for improved non-lethal personal defense devices.